Paul nordmann



(No Model.) I

P. NORDMANN.

ELECTRIC ARC LAMP.

N0. 498,566. Patented May 30, 1893.

INVENTOR WI T NESSE A TTORNE Y UNTTED STATES PATENT OFFICE,

PAUL NORDMANN, OF BERLIN, GERMANY, ASSIGNOR TO SIEMENS dz HALSKE, OF SAME PLACE.

ELECTRIC-ARC LAM P.

SPECIFICATION forming part of Letters Patent No. 498,566, dated May 30, 189 3.

Application filed November 10, 1892. Serial 110.452.222- (No model.) Patented in Germany January 24, 1890, No. 56,022 i in Austria-Hungary October 11, 1890, No. 5,438 and No. 28,316; in France October 15, 1890, No. 208,882; in Belgium October 15,1890,N0. 92,326, and in England 8eptember 12,1891,N0.17,940.

as before, but the current is then passed from To aZZ whom it may concern:

Be it known that 1, PAUL NORDMANN, a subject of the King of Prussia, German Emperor, residing at the city of Berlin, in the German Empire, have invented new and useful Improvements in Are Lamps, (for which I have obtained Letters Patent in Germany, No. 56,022, dated January 24, 1890; in France, No. 208,882, dated October 15, 1890; in Belgium, No. 92,326, dated October 15, 1890; in Austria, No. 5,438, dated October 11, 1890; in Hungary, No. 28,316, dated October 11, 1890, and in England, No. 17,940, dated September 12, 1891,) of which the following is aspecification.

In order to render arc lamps applicable for use on electric light distributingnetworks,in which a greater potential difference is used than is required for ordinary arc lamps, it has hitherto been necessary to reduce the eX- cessive tension by means of resistances; or to arrange several lamps in series, which were then dependent upon each other; that is to say, which required all to be in operation or out of operation at the same time.

My present invention consists in arranging two or more pairs of carbons in an arc lamp, in such a manner that the same current has to pass through them in series. Between each pair of carbons an arc is formed, and as a certain potential difference is required for each arc, the total potential difference of the lamp can be increased, as may be desired, by increasing the number of pairs of carbons.

Referring to the accompanying drawings which illustrate my invention, in which similar letters of reference indicate like parts, Figures 1 to 6 show diagrammatically various arrangements which may be employed for carrying out my invention.

Referring first to Fig. 1: two pairs of carbons are shown, the current in this construction being made first to pass into carbon No. 1, forming a luminous are between 1 and 2; from carbon 2, it passes to carbon 3,-which is positive,--and forms between 3 and 4 the second arc. Generally, I prefer to employ the arrangement shown in Fig. 2,p:a,rticularly where continuous currents are used. In this case, the first are is formed between 1 and 2,

carbon 2 up to carbon 4, thence to carbon 3, forming the second are.

Generally speaking, in lamps using continuous currents, the current should be arranged to pass in the same direction through both pairs of carbons, whereas in alternate current lamps, the simplest available arrangement may be chosen, irrespective of the direction of the currents.

Fig. 3 shows an arrangement with three pairs of carbons, the current being made to pass consecutively through all the three pairs, 2'. 6. through 1, 2; 4, 3; and 6, 5, in the same direction, as indicated.

In Fig. 4, there are two groups of carbons:

1, 1"; 2, 2, constituting one group; and 3, 3; 4, 4, constituting the second. The current is made to pass simultaneously through the two pairs of the first group, thus producing two luminous arcs, and then through the two pairs of the second group, producing two further luminous arcs. Or the two pairs of each group might also be connected in series instead of in parallel, as in simultaneously 0 Fig. 1, so as to cause the current to pass in Fig. 5 shows a moditi- 8o ating according to this invention,the essential feature being in all cases that the current is made to pass in series through two or more pairs of carbons so as to produce simultaneously two or more luminous arcs in one and the same lamp.

The regulation of a lamp of the above description can be effected by regulating all the carbons simultaneously, as shown in Figs. 1, 2, 3, 4 and 6, or in the usual manner, by regulating each pair of carbons, as shown in Fig. 5

5 or each group of pairs may have a rate regulating mechanism.

I have not shown any mechanism for regusepalating the carbons, as any mechanism such as is commonly used for the purpose may be employed.

In the case where two pairs of carbons are controlled by the same regulating apparatus, then in order to insure equal consumption of both pairs, regulating mechanism must be employed which will adjust the carbon holders in such manner that the sum of the arcs remains practically constant. It now, from some cause, the arc of the one pair has become longer than that of the other, the shorter arc Will always be less than the normal length and the longerarcmorethanthenormallength. As, however, the carbons of an arc lamp consume more quickly the longer the arc, there will always be a tendency to increase the difference once established between the two arcs. In order to obviate this defect, I may make use of the arrangement shown diagrammaticallyin Fig. 6. The current in this construction is made to pass through the carbon pairs 1, 2 and 4, 3. The carbons 1 and 4 are fixed in the upper carbon holder 10,

which can be raised and lowered, under the beam on the support 16 in such manner that it can turn through a certain angle. To each end of the carbon holder 15 are attached the armatures 17 and 18 of the electro-magnets; 19 and 20, which are arranged below them. By this arrangement, the electro-magnet 19 attracts the armature 17, which controls the are 41, 3, and is arranged in parallel with the are 1, 2. The electro-magnet 2O attracts the armature 18, which controls the are 1, 2, and

it is connected in parallel with the arc 4r, 3.

The operation of this device is as follows: As soon as, say, the are 4., 3 becomes longer than the are 1, 2, the electro-magnet 20, which is in shunt circuit to the are 4:, 3, will be subject to a greater tension than the electromagnet 19. The difference in the length of the two arcs, and consequently that of the two tensions will go 011 increasing until the attraction exerted by the electro n1agnet2O upon its armature 18 sufficiently exceeds the attraction exercised by the electro-magnet 19 upon its armature 17 to cause the position of the carbon holder 15 to-be changed. As, however, the attraction of an electro-magnet does not alone depend upon its excitation, but also upon the distance of the armature, the differencebetween theattractions exerted by the two electro-magnets will continue to increase as the armature 18 approaches the magnet 20, and the carbon holder 15 will consequently tilt over on that side until its limit of motion is reached. This limitation is so arranged that if the are 4, 3 is in the first instance greater than 1, 2, then after the tilting over, the are 1, 2 will be slightly greater than 4, 3. The

consequence will be that the are 1, 2 will new gradually increase until the difference in the action of the electro-magnets has become sufficiently great to cause the tilting over of the carbon holder 15 in the contrary direction, and this alternate action will continue until the carbons are entirely burned down. The difference between the length of the arcs can consequently never be greater than is permitted by the above sensitive device. This regulating mechanism can, of course, be applied to the upper carbon holder 10 instead of to the lower one, or it may be combined with the regulating mechanism 30 of the lamp in any suitable manner.

Having thus described my invention, I claim 1. An electric arc lamp having two or more pairs or groups of pairs of carbons connected in series, and in which two or more luminous arcs are simultaneously produced and maintained.

2. An electric arc lamp comprising two or more pairs or groups of pairs of carbons connected in series, and in which two or more luminous arcs are simultaneously produced and maintained, and mechanism for controlling each pair or group of pairs of carbons.

3. An electric arc lamp comprising two or more pairs or groups of pairs of carbons connected in series, and in which two or more luminous arcs are simultaneously produced and maintained, and a single mechanism for controlling all of the pairs or groups of pairs of carbons.

4. In an electric arc lamp, the combination with the upper carbons, adapted tomovc in unison, of corresponding carbons mounted opposite thereto so as to form two or more pairs or groups of pairs of carbons, the said pairs or groups of pairs connected in series, whereby two or more luminous arcs are simultaneously produced and maintained.

5. In an electric arc lamp, the combination of a single teed-rod, two or more carbons mounted thereon, two or more carbons mounted fixedly opposite said first named carbons, soas to form two or more pairs or groups of pairs of carbons, and said pairs or groups of pairs connected in series, whereby two or more luminous arcs are simultaneously producedand maintained.

6. An arc lamp having two or more pairs of carbons arranged in series, mechanism responsive to variations in the strength of the current transmitted through theseparate pairs of carbons, to vary the relative position of the carbons of the separate pairs as regards each other, and thus preserve the length of the are between each pair constant.

In testimonywhereof I have aflixed my signature in the presence of two witnesses.

PAUL NORDMANN. Witnesses:

KARL WAGNER, Gno. H. BENJAMIN. 

